Rotating contact assemblies for self-leveling camera heads

ABSTRACT

Camera heads and associated rotating contact assemblies are disclosed. In one embodiment a slip-ring assembly includes a rotating contact assembly including slip rings having a cylindrical ring assembly and a flexible or bendable brush assembly. Brush elements may flexed to remain in contact with corresponding ring assembly electrical contacts. Bush contacts may be coated or have attached contact assemblies to increase hardness and oxide resistance with materials such as palladium nickel, rhodium, or hard gold, though a variety of other materials may be used as a suitable coating.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. §119(e) to co-pendingU.S. Provisional Patent Application Ser. No. 61/740,438, entitledROTATING CONTACT ASSEMBLIES FOR SELF-LEVELING CAMERA HEADS, filed Dec.20, 2012, and to co-pending U.S. Provisional Patent Application Ser. No.61/780,865, entitled ROTATING CONTACT ASSEMBLIES FOR SELF-LEVELINGCAMERA HEADS, filed Mar. 13, 2013. The content of each of theseapplications is hereby incorporated by reference herein in it isentirety for all purposes.

FIELD

This disclosure relates generally to camera heads or other devicesincluding rotating contact assemblies. More specifically, but notexclusively, the disclosure relates to self-leveling camera heads orother devices employing rotating contact assemblies in the form of sliprings having a cylindrical ring assembly and a flexible or bendablebrush assembly.

BACKGROUND

Rotating contact assemblies using slip rings to provide electricalcontacts between moving elements are known in the art. Existing contactassemblies are typically complex in design, resulting in difficulties inmanufacture. Furthermore, the complexity of camera heads employingexisting rotating contact assemblies may also result in a larger thannecessary overall package and reduced reliability, requiring heavingweights in a self leveling camera using counterweights to self-level,resulting in heavier and/or larger camera heads or other devices.

As used in pipe inspection systems, self leveling camera heads may berequired to fit into small or constrained areas, such as within aclogged pipe or drain, thus placing larger camera heads at adisadvantage relative to smaller camera heads. In some applications,larger camera heads cannot be used at all due to their size, and in manyapplications a smaller camera head may provide advantages even when sizeis not a constraint. In addition, cameras and other devices utilizingrotating contact mechanisms known in the art may also suffer frompremature failure and greater electrical noise due to unwanted internaldirt and other debris.

Accordingly, there is a need in the art to address the above-describedas well as other problems.

SUMMARY

This disclosure relates generally to camera heads or other devicesincluding rotating contact assemblies. More specifically, but notexclusively, the disclosure relates to a self-leveling camera heads orother devices employing rotating contact assemblies in the form of sliprings having a cylindrical ring assembly and a flexible or bendablebrush assembly.

For example, in one aspect, a rotating contact assembly in accordancewith certain aspects may include an innovative brush-contact system. Insuch a brush-contact system, circuit board fabrication methods may beused for the manufacture of brush elements with electrical contacts,which may be flexed to remain in contact with corresponding ringassembly electrical contacts. These circuit board brush contacts may becoated or have attached contact assemblies to increase hardness andoxide resistance with, for instance, palladium nickel, rhodium, or hardgold, though a variety of other materials may be used as a suitablecoating.

In another aspect, a cylindrical ring assembly may include a pluralityof electrical contact surfaces which may be held in contact with thebrush assemblies to provide continuous electrical connectivity duringrotation of the ring assembly relative to the brush assembly.

In another aspect, a camera head which may employ the force of gravityto enable self leveling may be created using the previously mentionedbrush and ring contact system. In such camera heads, a rotating contactassembly employing this brush contact system may allow for rotations ofthe imaging component in order to self level, while maintainingelectrical connectivity between the rings contacts and brush contacts.

The geometry of a camera head in accordance with aspects of the presentdisclosure may result in a camera head of smaller overall package sizeand/or enhanced manufacturability and improved durability relative toprior art camera heads.

In another aspect, a video inspection system utilizing a self-levelingcamera head may be implemented in accordance with various aspects. Thevideo inspection system may be a pipe inspection system utilizing such aself-leveling camera.

In another aspect, the disclosure relates to a camera head. The camerahead may include, for example, a housing, an imager disposed within thehousing on a first element movable relative to the housing, a secondelement rotationally movable relative to the first element, the secondelement including an electrical output connection, and a slip ringcoupled between the first element and the second element to provide anelectrical connection between an output of the imager and the electricaloutput connection. The slip ring may include a cylindrical ring assemblyincluding one or more ring electrical contacts and a brush assemblydisposed around the cylindrical ring assembly. The brush assembly mayinclude one or more brush electrical contacts positioned in contact withcorresponding ones of the one or more ring electrical contacts. Thecamera head may further include a counterweight to self-level theimaging sensor via gravity.

In another aspect, the disclosure relates to a slip ring apparatus. Theslip ring apparatus may include, for example, a cylindrical ringassembly including one or more ring electrical contacts, and a brushassembly disposed around the cylindrical ring assembly, the brushassembly including one or more brush electrical contacts positioned incontact with corresponding ones of the one or more ring electricalcontacts.

In another aspect, grease and/or other debris trap material, such asflypaper or other materials may be disposed on or within a camera headand associated elements to prevent unwanted dirt and debris frominterfering with internal components to aid in preventing prematurefailure and/or unnecessary electrical noise. In some embodiments, thedebris trap material may include adhesive tape material.

In another aspect, the disclosure relates to a video inspection system.The video inspection system may include, for example, a video displayand a camera head. The camera head may include a housing, an imagerdisposed within the housing on a first element movable relative to thehousing, a second element rotationally movable relative to the firstelement, the second element including an electrical output connection,and a slip ring coupled between the first element and the second elementto provide an electrical connection between an output video signal ofthe imager and the electrical output connection. The slip ring mayinclude a cylindrical ring assembly including one or more ringelectrical contacts, and a brush assembly disposed around thecylindrical ring assembly, the brush assembly including one or morebrush electrical contacts positioned in contact with corresponding onesof the one or more ring electrical contacts. The video inspection systemmay further include a communications link between the camera head andthe video display system to couple the output video signal from theelectrical output connection to the video display system. Thecommunications link may be a wired or wireless communications link, suchas a wired cable or connector or wireless 802.11, Bluetooth, or otherwireless communications module.

Various additional aspects, features, and functionality are furtherdescribed below in conjunction with the appended Drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present application may be more fully appreciated in connection withthe following detailed description taken in conjunction with theaccompanying drawings, wherein:

FIG. 1 is an illustration of an operator using a pipe inspection systemwhich may include aspects of the disclosure;

FIG. 2 is a top down isometric view of an embodiment of an enhancedself-leveling camera head;

FIG. 3 is a top down exploded view of details of the camera headembodiment of FIG. 2;

FIG. 4 is a bottom up exploded view of details of the camera headembodiment of FIG. 2;

FIG. 5 is a top down exploded view of details of a front housingassembly embodiment;

FIG. 6 is a bottom up exploded view of details of the housing assemblyembodiment of FIG. 5;

FIG. 7 is a top down exploded view of a rear housing assemblyembodiment;

FIG. 8 is a bottom up exploded view of details of the rear housingassembly embodiment of FIG. 7;

FIG. 9A is a top down exploded view of details of a front self-levelingmodule embodiment;

FIG. 9B is a top down exploded view of details of an alternative frontself-leveling module embodiment;

FIG. 10A is a bottom up exploded view of details of the frontself-leveling module embodiment of FIG. 9A;

FIG. 10B is a bottom up exploded view of details of the frontself-leveling module embodiment of FIG. 9B;

FIG. 11 is a top down exploded view of details of a centralself-leveling module embodiment;

FIG. 12 is a bottom up exploded view of the central self-leveling moduleembodiment of FIG. 11;

FIG. 13 an isometric view of details of an embodiment of a brush contactmodule;

FIG. 14 is a top down exploded view of details of an embodiment of abrush contact module including brush elements having interlocking tinesor fingers;

FIG. 15 is a bottom up exploded view of details of the brush contactmodule embodiment of FIG. 14;

FIG. 16 is an isometric view of details of an embodiment of a rearself-leveling module including a cylindrical contact ring assembly;

FIG. 17 is a top down exploded view details of the self-leveling moduleembodiment of FIG. 16;

FIG. 18 is a bottom up exploded view of details of the self-levelingmodule embodiment FIG. 16;

FIG. 19 an isometric view illustrating details of an embodiment of acylindrical contact ring module;

FIG. 20 is a top down exploded view of details of the contact ringmodule embodiment of FIG. 19;

FIG. 21 is a bottom up exploded view of details of the contact ringmodule embodiment of FIG. 19;

FIG. 22 is a sectional view of details of the contact ring moduleembodiment of FIG. 19 taken along line 22-22;

FIG. 23 is an isometric view of details of an embodiment of a rotatingcontact element;

FIG. 24 is a sectional view of details of the rotating contact elementembodiment of FIG. 23 taken along line 24-24;

FIG. 25 is a sectional view of details of the rotating contact elementembodiment of FIG. 23 taken along line 25-25;

FIG. 26 is an exploded view of details of the rotating contact elementembodiment of FIG. 23;

FIG. 27 is a front isometric view details of an embodiment of a PCBbrush element with bifurcated trace attachments;

FIG. 28 is a front isometric view of details of an embodiment of a pairof interleaving PCB brush elements;

FIG. 29 is an isometric view of the interleaved PCB brush elementembodiments of FIG. 28 situated as they may be made to bend or flexabout an assembly of an embodiment of a cylindrical ring assemblyincluding a contact guide cap, contact rings, and dielectric separatorrings;

FIG. 30 is a sectional view of details of the embodiment of FIG. 29along line 30-30.

FIG. 31A illustrates details of an example embodiment of elements of aslip ring assembly from a side view in accordance with certain aspects;

FIG. 31B illustrates details of the slip ring assembly embodiment ofFIG. 31A from a top view;

FIG. 32 illustrates details of another embodiment of a slip ringassembly in accordance with certain aspects, including a brush elementwith multiple interweaved tines or fingers;

FIG. 33 illustrates details of an example embodiment of a camera headincluding aspects of the disclosure usable for miniaturization, alongwith similar prior art camera head and coins to illustrate relativesize;

FIG. 34 illustrates details of an embodiment of components of a camerahead interior including a cylindrical ring assembly, along with coins toillustrate relative size;

FIG. 35 illustrates details of an embodiment of components of a camerahead interior including a brush module and flexible printed circuitboard brushes, along with coins to illustrate relative size; and

FIG. 36 illustrates details of an embodiment of a flexible printedcircuit board brush element along with coins to illustrate relativesize.

DETAILED DESCRIPTION OF EMBODIMENTS

This disclosure relates generally to camera heads or other devicesincluding rotating contact assemblies. More specifically, but notexclusively, the disclosure relates to a self-leveling camera heads orother devices employing rotating contact assemblies in the form of sliprings having a cylindrical ring assembly and a flexible or bendablebrush assembly.

Various details of the disclosure herein may be combined with inspectioncamera systems and components such as those described in co-assignedpatents and patent applications including U.S. Pat. No. 6,697,102,issued Feb. 24, 2004, entitled BORE HOLE CAMERA WITH IMPROVED FORWARDAND SIDE VIEW ILLUMINATION, U.S. Pat. No. 6,831,679, issued Dec. 14,2004, entitled VIDEO CAMERA HEAD WITH THERMAL FEEDBACK LIGHTING CONTROL,U.S. Pat. No. 6,862,945, issued Mar. 8, 2005, entitled CAMERA GUIDE FORVIDEO PIPE INSPECTION SYSTEM, U.S. Pat. No. 6,958,767, issued Oct. 25,2005, entitled VIDEO PIPE INSPECTION SYSTEM EMPLOYING NON-ROTATING CABLEDRUM STORAGE, U.S. patent application Ser. No. 11/928,818, filed Oct.30, 2007, entitled PIPE MAPPING SYSTEM, U.S. Patent Application No.61/034,907, filed Mar. 7, 2008, entitled PIPE INSPECTION IMAGING SYSTEM,U.S. patent application Ser. No. 12/704,808, filed Feb. 12, 2010,entitled PIPE INSPECTION SYSTEM WITH REPLACEABLE CABLE STORAGE DRUM,U.S. patent application Ser. No. 12/399,859, filed Mar. 6, 2009,entitled PIPE INSPECTION SYSTEM WITH SELECTIVE IMAGE CAPTURE, U.S.patent application Ser. No. 12/975,496, filed Jun. 8, 2012, entitledMulti-Camera Pipe Inspection Apparatus, Systems, & Methods, U.S. patentapplication Ser. No. 13/358,463, filed Jan. 25, 2012, entitledSELF-LEVELING INSPECTION SYSTEMS AND METHODS, U.S. Provisional PatentApplication Ser. No. 61/740,438, filed Dec. 20, 2012, entitled ROTATINGCONTACT ASSEMBLIES FOR SELF-LEVELING CAMERA HEADS and U.S. patentapplication Ser. No. 13/358463, filed Jan. 25, 2012, entitledSelf-Leveling Inspection Systems and Methods. The content of each ofthese applications is incorporated by reference herein in its entirety.These applications may be individually or collectively referred toherein as the “incorporated applications.”

Example details of pipe inspection system and associated self-levelingcamera head apparatus are described in the incorporated applications,and may be combined with the disclosures herein in various embodiments.

Overview

This disclosure relates generally to camera heads or other devicesincluding rotating contact assemblies. More specifically, but notexclusively, the disclosure relates to a self-leveling camera heads orother devices employing rotating contact assemblies in the form of sliprings having a cylindrical ring assembly and a flexible or bendablebrush assembly.

The following exemplary embodiments are provided for the purpose ofillustrating examples of various aspects, details, and functions of thepresent disclosure; however, the described embodiments are not intendedto be in any way limiting. It will be apparent to one of ordinary skillin the art that various aspects may be implemented in other embodimentswithin the spirit and scope of the present disclosure.

In one aspect, a rotating contact assembly in accordance with certainaspects may include an innovative brush-contact system. In such abrush-contact system, circuit board fabrication methods may be used forthe manufacture of brush elements with electrical contacts, which may beflexed to remain in contact with corresponding ring assembly electricalcontacts. These circuit board brush contacts may be coated or haveattached contact assemblies to increase hardness and oxide resistancewith, for instance, palladium nickel, rhodium, or hard gold, though avariety of other materials may be used as a suitable coating.

In another aspect, a cylindrical ring assembly may include a pluralityof electrical contact surfaces which may be held in contact with thebrush assemblies to provide continuous electrical connectivity duringrotation of the ring assembly relative to the brush assembly.

In another aspect, strategically place grease and/or other debris trapmaterial, such as flypaper, may be used to prevent unwanted dirt anddebris from interfering with internally components to aid in preventingpremature failure and/or unnecessary electrical noise. In someembodiments, the debris trap material may include adhesive tapematerial.

In another aspect, a camera head which may employ the force of gravityto enable self leveling may be created using the previously mentionedbrush and ring contact system. In such camera heads, a rotating contactassembly employing this brush contact system may allow for rotations ofthe imaging component in order to self level, while maintainingelectrical connectivity between the rings contacts and brush contacts.

The geometry of a camera head in accordance with aspects of the presentdisclosure may result in a camera head of smaller overall package sizeand/or enhanced manufacturability and improved durability relative toprior art camera heads.

In another aspect, a video inspection system utilizing a self-levelingcamera head may be implemented in accordance with various aspects. Thevideo inspection system may be a pipe inspection system utilizing such aself-leveling camera.

In another aspect, the disclosure relates to a camera head. The camerahead may include, for example, a housing, an imager disposed within thehousing on a first element movable relative to the housing, a secondelement rotationally movable relative to the first element, the secondelement including an electrical output connection, and a slip ringcoupled between the first element and the second element to provide anelectrical connection between an output of the imager and the electricaloutput connection. The slip ring may include a cylindrical ring assemblyincluding one or more ring electrical contacts and a brush assemblydisposed around the cylindrical ring assembly. The brush assembly mayinclude one or more brush electrical contacts positioned in contact withcorresponding ones of the one or more ring electrical contacts. Thecamera head may further include a counterweight to self-level theimaging sensor via gravity.

The brush assembly may include, for example, one or more brush elements.The brush electrical contacts may be on or within the brush element. Thebrush element may include a plurality of tines or fingers. The pluralityof tines or fingers may be configured to intertwine with tines orfingers of other brush elements in the brush assembly. The electricalcontacts may be electrical signal pads or traces on the tines orfingers. The brush assembly may include a plurality of brush elementshaving fingers or tines, wherein the fingers or tines of the brushelements are interleaved in the brush assembly. The interleaved fingersor tines of the plurality of brush elements may include redundantelectrical contacts relative to the cylindrical ring assembly electricalcontacts.

The brush element may, for example, include a printed circuit board(PCB). The electrical contacts may be electrically conductive areas onor within the PCB. The electrical contacts may be wires or otherelectrical conductors attached or coupled to the PCB. The electricallyconductive areas on the PCB may be electrical circuit pads or traces.The brush electrical contacts and/or cylindrical ring electricalcontacts may be coated with one or more of palladium, nickel, rhodium,hard gold, or other similar or equivalent materials to decreasefrictional contact erosion and/or corrosion.

The cylindrical ring assembly may include, for example, one or moreelectrical contacts. The electrical contacts may be contacts on one ormore contact rings. The cylindrical ring assembly may include aplurality of contact rings. The cylindrical ring assembly may includeone or more dielectric separate rings. The cylindrical ring assembly mayfurther include a contact guide cap.

In another aspect, the disclosure relates to a slip ring apparatus. Theslip ring apparatus may include, for example, a cylindrical ringassembly including one or more ring electrical contacts, and a brushassembly disposed around the cylindrical ring assembly, the brushassembly including one or more brush electrical contacts positioned incontact with corresponding ones of the one or more ring electricalcontacts.

The brush assembly may include, for example, one or more brush elements.The brush electrical contacts may be on or within the brush element. Thebrush element may include a plurality of tines or fingers. The pluralityof tines or fingers may be configured to intertwine with tines orfingers of other brush elements in the brush assembly. The electricalcontacts may be electrical signal pads or traces on the tines orfingers. The brush assembly may include a plurality of brush elementshaving fingers or tines, wherein the fingers or tines of the brushelements are interleaved in the brush assembly. The interleaved fingersor tines of the plurality of brush elements may include redundantelectrical contacts relative to the cylindrical ring assembly electricalcontacts.

The brush element may, for example, include a printed circuit board(PCB). The electrical contacts may be electrically conductive areas onor within the PCB. The electrical contacts may be wires or otherelectrical conductors attached or coupled to the PCB. The electricallyconductive areas on the PCB may be electrical circuit pads or traces.The brush electrical contacts and/or cylindrical ring electricalcontacts may be coated with one or more of palladium, nickel, rhodium,hard gold, or other similar or equivalent materials to decreasefrictional contact erosion and/or corrosion.

The cylindrical ring assembly may include, for example, one or moreelectrical contacts. The electrical contacts may be contacts on one ormore contact rings. The cylindrical ring assembly may include aplurality of contact rings. The cylindrical ring assembly may includeone or more dielectric separate rings. The cylindrical ring assembly mayfurther include a contact guide cap.

In another aspect, the disclosure relates to a video inspection system.The video inspection system may include, for example, a video displayand a camera head. The camera head may include a housing, an imagerdisposed within the housing on a first element movable relative to thehousing, a second element rotationally movable relative to the firstelement, the second element including an electrical output connection,and a slip ring coupled between the first element and the second elementto provide an electrical connection between an output video signal ofthe imager and the electrical output connection. The slip ring mayinclude a cylindrical ring assembly including one or more ringelectrical contacts, and a brush assembly disposed around thecylindrical ring assembly, the brush assembly including one or morebrush electrical contacts positioned in contact with corresponding onesof the one or more ring electrical contacts. The video inspection systemmay further include a communications link between the camera head andthe video display system to couple the output video signal from theelectrical output connection to the video display system. Thecommunications link may be a wired or wireless communications link, suchas a wired cable or connector or wireless 802.11, Bluetooth, or otherwireless communications module.

Some embodiments may use a lubricant on slip contact surfaces, such asSuperlube with include PTFE (Teflon). Low temperature, compliant soldermay be used to ease assembly and reduce likelihood of failure duringimpacts, such as when a camera head in a pipe inspection system impactsa pipe obstruction or is dropped by a user. Example solder materialsinclude, but are not limited to, Alpha WS-852 and Indium Corp. Alloys281 or 282.

A dessicant may be included internally in the camera housing to removemoisture and reduce fogging and/or corrosion internal to the camerahead. Bearings within the camera head or coupled to the camera head foruse with moving parts may be ball bearings, and the ball bearings may bemetal or ceramic balls. Ceramic balls may advantageously lower weightand/or provide better impact resistant. A light oil on the bearings mayprovide both frictional improvements and act as a damping agent to limitrotational oscillations of elements such as leveling mechanisms duringimpacts or accelerations. An oven reflow process may be used to providepotential advantages in manufacturing.

Although the position of the brushes and rings are shown in a particularexemplary configuration and described accordingly herein, in someembodiments they may be swapped or interchanged, in whole or in part.

Various additional aspects, features, and functionality are furtherdescribed below in conjunction with the appended Drawings.

It is noted that as used herein, the term, “exemplary” means “serving asan example, instance, or illustration.” Any aspect, detail, function,implementation, and/or embodiment described herein as “exemplary” is notnecessarily to be construed as preferred or advantageous over otheraspects and/or embodiments.

Example Rotating Contact Assemblies for Self-Leveling Camera Heads

Turning to FIG. 1, one application for a rotating contact assembly inkeeping with aspects of the present disclosure may include a pipeinspection system using a self-leveling camera head. FIG. 1 illustratesone example embodiment 100 of such a pipe inspection system. Pipeinspection system 100 may include a self-leveling camera head 110secured to a push-cable 120 that further connects to a push-cable reel130 such that a user 140 may dispense the self-leveling camera head 110and push-cable 120 into an area being expected, such as the interior ofpipe 150 as shown (or other inspection areas, such as the interiors ofpipes, conduits, cavities, inside walls, etc.). In some pipe inspectionsystems, such as pipe inspection system 100, a camera control unit(“CCU”), such as the camera control unit 160 as shown, may be used tomonitor video feed from within the pipe 150. Data such as video, images,audio signals, environmentally sensed conditions, and the like may betransferred from the camera head 110 to the CCU (or other coupledcomputer-based devices) for display, storage, transmission to othersystems, and the like.

In order to facilitate rotating contacts in a camera head such as camerahead 110 (or in other applications requiring rotating contacts or slipring type connections), camera head 110 may include a slip ring assemblycomprising a cylindrical ring assembly and corresponding brush assembly,wherein the cylindrical ring assembly rotates, relative to the brushassembly, about an axis, while electrical contacts on the ring assemblymaintain an electrical signal path to corresponding contacts on thebrush assembly during axial rotation of the cylindrical ring assembly.

The slip ring assembly may include one or more ring electrical contactsand a brush assembly disposed around the cylindrical ring assembly. Thebrush assembly may include one or more brush electrical contactspositioned in contact with corresponding ones of the one or more ringelectrical contacts in various configurations.

For example, FIG. 31A illustrated details of an embodiment of a brushassembly 3100 and corresponding cylindrical ring assembly 3110, whichmay form the core elements of a slip ring for use in self-levelingcamera heads, such as camera head 110 of FIG. 1. As shown in FIG. 31A,the slip ring assembly may include one or more brush elements 3130. Inthis example embodiment, two brush elements 3130 may be used as shown infurther detail in FIG. 31B, with the two brush elements denoted 3130-1and 3130-2. Brush element 3130-2 is omitted from FIG. 31A for clarity.In some embodiments, lubricant may be used on various slip ring assemblysurfaces.

The brush elements 3130 may include one or more electrical contacts 3132(in this example, three electrical contacts, 3132-1, 3132-2, and 3132-3are shown, however, other numbers and/or shapes of the electricalcontacts may be used in various embodiments) disposed on or within thebrush element 3130. In an exemplary embodiment, the contacts 3132 may beelectrical traces of various shapes and/or sizes on a printed circuitboard substrate. Other embodiments may include contacts on a flexcircuit substrate or other substrate material on which electricalcontacts may be formed or etched on or attached to. The electricalcontacts 3132 may include holes 3133 or other termination elements toelectrically connect the contacts 3132 to wires 3134 (as shown) and/orother electrical circuit elements, such as pads on other electroniccircuit elements, mechanical terminals, frictional electrical contacts,or other electrical contact mechanisms. In the example shown, threewires 3134-1, 3134-2, and 3134-3 are shown to couple the electricalcontacts to other electrical circuit elements, such as output connectorson the camera head, output wires, electrical circuit components such asintegrated circuits, active or passive electronic components, and thelike.

The cylindrical electrical ring assembly 3110 may include correspondingelectrical contacts 3112 (in this example, 3112-1, 3112-2, 3112-3) whichmay be electrically connected to wires 3114 (e.g., to correspondingwires 3114-1, 3114-2, and 3114-3) or other electrical connections. Theelectrical contacts 3112 are positioned to be in electrical contact withcorresponding electrical contacts 3132 on the brush elements to maintainelectrical connectivity during rotation of the ring assembly 3110,relative to the brush assembly and brush elements 3130, about rotationalaxis 3113. The brush elements may be flexible or bendable tocontinuously maintain the electrical contacts between the brush elementsand cylindrical ring assembly during rotation of the ring assembly 3110via a “squeezing action” of the brush elements on the ring assembly.

FIG. 31B illustrates additional details of the slip ring embodiment ofFIG. 31A from a top view. As shown in FIG. 31B, the brush element 3130-1and 3130-2 may be fixed at or near the end areas 3160, such as via pins,block 3120 (as shown), straps, screws, brackets, or other mechanicalattachment mechanisms. By bending or flexing the brush elements 3130around the cylindrical ring assembly 3110, a squeezing action may applytension between the brush assembly and ring assembly to maintain theelectrical contacts when the ring assembly is rotated. Electricaloutputs from the brush elements and ring assembly may be coupled towires (e.g., wires 3134 and/or 3114) or to other electrical connectiontypes, such as circuit board pads, electrical or electronic circuitcomponents, and the like.

FIG. 32 illustrates details of another embodiment of the core elementsof a slip ring assembly wherein a brush assembly 3230 including twobrush elements 3250 and 3260 include interleaved tines or fingers 3251and 3253, with corresponding electrical contacts 3252, 3254 on thefingers. Various combinations of fingers and contacts may be used invarious embodiments so as to provide electrical connections between thebrush elements and electrical contacts of the corresponding ringassembly 3210 during rotation of the ring assembly 3210 about arotational axis (relative to the brush assembly).

Attention is now directed to FIGS. 2-4, which illustrate details of anexemplary embodiment of a self leveling camera head including a slipring assembly having a cylindrical ring assembly and corresponding brushassembly, in accordance with certain aspects. As shown in FIGS. 2-4,camera head embodiment 200, which may correspond with camera head 110 ofFIG. 1, may include a front housing assembly 210 and a rear housingassembly 220. In operation, an imaging sensor of the camera head mayrotate relative to other elements of the camera head, such as thehousing or other outer assembly, to provide self leveling. This may bedone by using an asymmetric weighting element within the camera head toallow gravity to orient the sensor in an upright position irrespectiveof the position of the housing and/or coupled push-cable.

As best illustrated in FIGS. 3 and 4, the camera head embodiment 200 mayinclude a front self-leveling inner case 330, a central self-levelingmodule 340, and a rear self-leveling inner case 350. The camera headembodiment 200 may also include an optional debris trap such as thedebris tape trap 335. In assembly, the central self-leveling module 340may be configured to largely rotate freely in respect to the frontself-leveling inner case 330 and the rear self-leveling inner case 350.Wires 360 may electrically couple electrical components mounted onto thefront self-leveling inner case 330 and the rear self-leveling inner case350. A shrink film cover 370 may be made to secure about the frontself-leveling inner case 330, central self-leveling module 340 (whichmay include a brush assembly as described herein), rear self-levelinginner case 350 (which may include a cylindrical ring assembly asdescribed herein), and wires 360 thus aiding in securing thesecomponents together. In assembly, a series of housing O-rings 380 may bemade to be seated between the front housing assembly 210 and the rearhousing assembly 220 providing a water-tight seal and protect internalcomponents. Furthermore, a rear self-leveling module O-ring 390 may beseated underneath the rear self-leveling inner case 350.

The debris tape trap 335 may be secured within self-leveling inner case330 so as not to interfere with movements of other internal components.The debris tape trap may scavenge dirt and debris and aid in preventingpremature failure or unwanted electrical noise. Grease may also beapplied to surfaces, such as the bottom surface of the rearcounterweight piece 1160 of FIG. 11, to act in a similar manner. Inalternative embodiments, grease and/or other adhesive trap material maybe used in numerous locations throughout the device to prevent unwanteddirt and debris from interfering with internally components.

Turning to FIGS. 5-6, the front housing assembly 210 may include a frontbezel piece 505 which is largely dome shaped with a hole formedcentrally within the dome. The front housing assembly 210 may, in part,further include a transparent illumination window 510, an LED reflector515, a light module PCB 520 with several light emitting diodes or LEDs525 and contact traces, such as the inner trace 520 a and outer trace520 b, and a retaining ring 530. The illumination window 510, LEDreflector 515, light module PCB 520 and retaining ring 530 may all belargely toroidal in shape and dimensioned to secure within the topopening of the front bezel piece 505 via threads on the LED reflector515 mating with threads on the on the front bezel piece 505. Theillumination window 510 may comprise a material with translucent ortransparent properties allowing light to pass though from powered LEDs525 on the light module PCB 520.

In assembly, the LED reflector 515 may be positioned between theillumination window 510 and light module PCB 520. Holes formed throughon the surface of the LED reflector 515 may be formed to allow each LED525 to pass through and effectively illuminate the work area when inuse. The LED reflector 515 may further be composed of or coated withreflective material allowing light from the LEDs 525 to more effectivelylight the work area. The retaining ring 530 may screw into place behindthe light module PCB 520 securing the illumination window 510, LEDreflector 515, light module PCB 520 with attached LEDs 525, andretaining ring 530 together. The retaining ring 530 may be sized toallow the electrical connection from the front self-leveling inner case330 (FIG. 3). A large O-ring 535 may be fitted between the illuminationwindow 510 and the front bezel piece 505 to provide a water-tight sealto internal components.

The toroidal shape of the illumination window 510 may allow for a windowtube 540 to be seated within. A window retaining piece 545 and animaging window 550 may further be secured to the window tube 540. Theimaging window 550 may comprise a material with translucent ortransparent properties such as sapphire allowing the internal camera ofthe camera head 200 (FIG. 2) a forward field of view. Between theillumination window 510 and the window tube 540 and between the windowretaining piece 545 and the imaging window 550, an O-ring 555 may beseated to aid in providing a water tight seal to internal components.

As shown in FIGS. 7 and 8, the rear housing assembly 220 may include arear housing element 710, which may be substantially cylindrical in anexemplary embodiment, along with a connector O-ring 720, pin connector730, a snap ring 740, and a large connector O-ring 750. In assembly,threads formed along the top of the rear housing element 710 may be madeto mate with threads formed within the front bezel piece 505 (FIG. 5)thus securing the components together.

Turning to FIGS. 9A and 10A, the front self-leveling inner case 330 mayfurther include a front module housing piece 910, a front module PCB920, and a front module bearing element 930. A series of inner springcontacts 925 a and outer spring contacts 925 b may also be secured tothe front module PCB 920. The front module housing piece 910 may belargely cylindrical in shape with a circular opening formed centrallyalong the top. The front module housing piece 910 may be dimension tolargely accommodate the components of the central self-leveling module340 (FIG. 3) within and may allow a lens module 1110 (FIG. 11) to fitthrough the top central opening. The front module PCB 920 may be annularin shape and be seated within a grooved section about the top centralopening of the front module housing piece 910. The front module bearingelement 930 may secure within the front module housing piece 910 and mayallow the central self-leveling module 340 (FIG. 3) to rotate in respectto the front self-leveling inner case 330. The front module bearingelement 930 may utilize steel or ceramic ball bearings. In someembodiments, the front module housing piece 910 may be molded ormachined plastic or aluminum.

Turning to FIGS. 9B and 10B, an alternative front module housingembodiment 950 may include a cross hole 955. The cross hole 955 mayallow a pin (not illustrated) to be inserted so as to stop the rotationand allow focusing of the lens.

Turning to FIGS. 11 and 12, the central self-leveling module 340 mayfurther include a lens module 1110, a front counterweight piece 1120, animaging module 1130, a series of screws 1140, a brush contact module1150 (which may include a brush assembly with brush elements asdescribed herein), desiccant paper 1155 and a rear counterweight piece1160. The imaging module 1120 may include a series of electricalcontacts such as the imaging module contact 1130 a, the imaging modulecontact 1130 b, and the imaging module contact 1130 c best illustratedin FIG. 12, so as to pass electrical signals and/or power between theimaging module 1130 and the brush contact module 1150. A brush modulecontact 1325 a, a brush module contact 1325 b, and a brush modulecontact 1325 c as best illustrated in FIG. 13 may make contact with theimaging module contact 1130 a, the imaging module contact 1130 b, andthe imaging module contact 1130 c. Threads formed along the bottom ofthe lens module 1110 may be made to mate with threads formed centrallyabout the top of the front counterweight piece 1120 to secure the lensmodule 1110 and the front counterweight piece 1120 together. Thedesiccant paper 1155 may be placed within the rear counterweight piece1160 and below the brush contact module 1150 so as to aid in preventingcorrosion and/or fogging of the lens.

The front counterweight piece 1120 may be formed with a half-circleridge formed along one edge which may provide additional mass along oneside of the central self-leveling module 340. The rear counterweightpiece 1160 may be formed with a pocket along one side designed to fit abrush contact module 1310 (FIG. 13) and provide an asymmetry in massalong the same side as the front counterweight piece 1120. The frontcounterweight piece 1120 and the rear counterweight piece 1160 mayfurther be composed of dense materials such as, but not limited to,steel, zinc, brass, tungsten, or filled plastics. As the centralself-leveling module 340 may be made to rotate freely in respect to thefront self-leveling inner case 330 (FIG. 3) and the rear self-levelinginner case 350 (FIG. 3), when in use, the asymmetry in mass along oneside of the front counterweight piece 1120 and the rear counterweightpiece 1160 may allow for the forces of gravity to operate as theleveling force of the camera head 200 (FIG. 2). The imaging module 1130may secure to the front counterweight piece 1120 through the use of thescrews 1140. The brush contact module 1150 may be seated within a pocketformed on the rear counterweight piece 1160. The rear counterweightpiece may, in turn, secure to the bottom of the front counterweightpiece 1120. The brush module contact 1325 a, brush module contact 1325b, and/or brush module contact 1325 c may make contact with the imagingmodule contact 1130 a, the imaging module contact 1130 b, and/or theimaging module contact 1130 c so as to pass electrical signals and/orpower between the imaging module 1130 and the brush contact module 1150.

As shown in detail in FIGS. 13-15, the brush contact module 1150 mayfurther include a brush cartridge 1310, a contact PCB 1320, and a seriesof brush elements, in the form of flexible PCB brushes 1330. The brushcartridge 1310 and the contact PCB 1320 may be formed with a centralopening allowing components of the rear self-leveling inner case 350(FIG. 3) to fit within. The PCB brushes 1330 may fit within groovesthrough the brush cartridge 1310 and make contact with components of therear self-leveling inner case 350 (FIG. 3) so as to pass electricalsignals and/or power from the rear self-leveling inner case 350 (FIG. 3)to the central self-leveling module 340 (FIG. 3).

The PCB brushes 1330 may comprise printed circuit board material orother flexible materials which may also be coated to increase hardnessand increase oxide resistance, particularly on the brush electricalcontacts. For instance, the PCB brushes 1330 may be coated withpalladium nickel, rhodium, or hard gold or other such materials. Printedcircuit board technologies and manufacturing processes may beparticularly suited to the fabrication of contact brushes, such as thePCB brushes 1330, due to the variety of parameters readily customizableto fit the specific application of the contact brush. For instance,substrate thickness, substrate material, width and length of the bendingelements, and shape or geometry of the contact brush are parameterswhich may be readily customized to fit a particular application. Acontact-brush system such as that of the brush contact module 1150 mayprovide enhancements to the ease and cost of manufacturing self-levelingcameras such as the camera head embodiments of the present disclosure.

In this exemplary embodiment there are two PCB brushes 1330, each withthree tines or fingers on the PCB brushes 1330 such that each tine mayprovide a separate electrical pathway. In alternative embodiments thenumber of tines providing electrical pathways may be changed to suit theparticular application. Furthermore, in some alternative embodiments,two or more PCB brushes may be used in a brush assembly, and contacts onthe two or more brushes may be redundant to further improve electricalconnectivity and/or operational reliability or endurance/wearresistance. In some embodiments, the PCB brushes may be oppositelymounted to mitigate impacts and shock from lifting both contacts at thesame time.

Turning to FIGS. 16-18, the rear self-leveling inner case 350 mayfurther include a rear module housing piece 1610, a rear bearing element1620 which may utilize ceramic balls, a series of pin contact sockets1630, a rear module PCB 1740 (FIGS. 17 and 18), a contact ring PCB 1650,and a cylindrical contact ring assembly including a contact guide cap1660, a series of contact rings 1670, and a series of dielectricseparator rings 1680. Electrical contact of the cylindrical contact ringassembly may be positioned in contact with corresponding electricalcontacts of the brush assembly to provide continuous electricalconnectivity during rotation of the cylindrical contact ring assemblyrelative to the brush assembly. In fabrication, the rear bearing element1620 may be seated within the rear module housing piece 1610 such as toallow the central self-leveling module 340 (FIG. 3) to rotate freely inrespect to the front self-leveling inner case 330 (FIG. 3) and the rearself-leveling inner case 350. Hand solder or solder reflow techniquesmay be used to connect contact rings 1670 to solder points 1755 on PCB1650.

The pin contact sockets 1630 may be made to pass through holes formedthrough the rear module housing piece 1610 and the rear module PCB 1740(FIGS. 17 and 18) so as to make contact with pin connector 730 (FIG.7)of the rear housing assembly 220 (FIG. 7). The pin contact sockets 1630may further make contact with contacts on the rear module PCB 1740(FIGS. 17 and 18) creating a pathway for electrical current from the pinconnector 730 (FIG. 7) of the rear housing assembly 220 (FIG. 7) to therear self-leveling inner case 350. The contact ring PCB 1650 may beseated centrally on the rear module PCB 1740 (FIGS. 17 and 18). Thecontact ring assembly including guide cap 1660, contact rings 1670, anddielectric separator rings 1680 may be configured to be secured to anupward extending arm of the contact ring PCB 1650.

As best illustrated in FIGS. 19-22, a contact ring module 1900 mayinclude a PCB and cylindrical contact ring assembly, such as rear modulePCB 1740, the contact ring PCB 1650, the contact guide cap 1660, thecontact rings 1670, and the dielectric separator rings 1680. The contactring PCB 1650 may be seated centrally within the rear module PCB 1740along a plane perpendicular to that of the rear module PCB 1740.Electrical pathways may be formed between the rear module PCB 1740 andthe contact ring PCB 1650 that extend internally within the contact ringPCB 1650. The internal electrical pathways of the contact ring PCB 1650may each connect to one of a series of contact pads 1755 (FIG. 20) onthe outer surface(s) of the contact ring PCB 1650.

In assembly, the contact rings 1670 and dielectric separator rings 1680may be seated on the upward extending arm of the contact ring PCB 1650in an alternating sequence so that each of the contact rings 1670 may beseparated by one of the dielectric separator rings 1680. Electricalpathways may be formed from the rear module PCB 1740 through the contactring PCB 1650 and to each of the contact rings 1670 creating pathways topass from the rear housing assembly 220 (FIG. 3) through the rearself-leveling inner case 350 (FIG. 3). These electrical pathways maythen pass through the brush contact module 1150 (FIG. 11) to the imagingmodule 1130 (FIG. 11) within the central self-leveling module 340 (FIG.11).

It is noted in this exemplary embodiment there are a total of three ofthe contact rings 1670. However, in alternative embodiments the numberof contacts rings may be increased or decreased to suit the number ofelectrical pathways as required by a particular application. Inaddition, redundant contact rings may be used to provide additionalelectrical pathways. The contact pads 1755 (FIG. 20) may be formed onthe contact ring PCB 1650 such that one of each of the contact rings1670 may be secured to the contact ring PCB 1650 about each of thecontact pads 1755 (FIG. 20). For instance, solder such as the solder2210 (FIG. 22) may be used to secure one contact ring 1670 to eachcontact pad 1755 (FIG. 20) of the contact ring PCB 1650. An electricalpathway may thereby be created through the contact pads 1755 (FIG. 20)to each of the contact rings 1670. In some embodiments, low temperature,compliant solder may be used to increase ease of assembly as well asdurability. Examples of such solder may be found in WS-852 from Alpha®and/or Indium Corporation Indalloy® 281 or 282.

Turning to FIGS. 23-26, a rotating contact element 2300 in accordancewith aspects of the present disclosure may include brush contact module1150 and contact ring module 1900. When assembled, the contact guide cap1660, the contact rings 1670, and dielectric separator rings 1680 seatedalong the upward extending arm of the contact ring PCB 1650 may beseated within the central opening formed through the brush cartridge1310 and the contact PCB 1320. Each of the contact rings 1670 may beposition such that each contact ring 1670 may contact pathways on onetine of each of the PCB brushes 1330. As best illustrated in FIG. 25,each tine of the PCB brushes 1330 may be made to bend and flex about thecontact rings 1670. Printed circuit board technologies and manufacturingprocesses may be particularly suited to the fabrication of contactbrushes, such as the PCB brushes 1330, due to the variety of parametersreadily customizable to fit the specific application of the contactbrush. For instance, substrate thickness, substrate material, width andlength of the bending elements, and shape or geometry of the contactbrush are parameters which may be readily customized to fit a particularapplication. In use, as the central self-leveling module 340 (FIG. 3)may be made to rotate freely in respect to the front self-leveling innercase 330 (FIG. 3) and the rear self-leveling inner case 350 (FIG. 3),the PCB brushes 1330 may continue to make contact with the contact rings1670 as rotations from self-leveling occur.

In some alternative embodiments, the contact area between the PCB brushor brushes and contact rings may be enhanced in various ways that may,for instance, create redundancy in electrical contact with the contactring, increase durability of the PCB brush at this contact area, and/orreduce friction between the PCB brush and contact rings. These contactarea enhancements may include, but are not limited to, wire bonding apattern of gold wires, attaching of short sections of silver wire tosignal traces, and/or attaching micro blocks of silver graphite to thecontact areas. In FIG. 27, the PCB brush 2700 contains a series ofsignal traces 2710 onto which a trifurcated wire bonding attachment 2720may be secured along the area of contact between the PCB brush 2700 anda contact ring. As one signal trace 2710 may run down each of the threetines of the PCB brush 2700, a total of three trifurcated wire bondingattachments 2720 may be used in each contact area along each tine. Inalternative embodiments, a different quantity of tines, signal traces,and attachments may be used. The trifurcation of the bonded wires witheach trifurcated wire bonding attachment 2720 may allow for redundancyin electrical contact made with a contact ring.

Redundancy in electrical contacts with contact rings may also beachieved by creating multiple PCB brushes with interleaving tines suchthat multiple contacts may be made with each contact ring. Asillustrated in FIGS. 28-30, a left PCB brush 2810 and a right PCB brush2820 may be made such that the tines of each may interleave. Signaltraces, such as the left PCB signal traces 2830 and the right PCB signaltraces 2840, may run along the length of each tine such that each signaltrace is offset nearest its redundant signal trace on the opposite PCBbrush. For example, the left PCB brush signal traces 2830 may run alongthe lower section of each tine of the left PCB brush 2810 whereas theredundant right PCB brush signal traces 2840 may run along the uppersection of each tine on the right PCB brush 2820. The top tines, middletines, and bottom tines of the left PCB brush 2810 and the right PCBbrush 2820 with offset signal traces may thereby make electrical contactwith a top, middle, and bottom ones of the contact rings 2910 (FIGS. 29and 30) respectively. As illustrated in FIGS. 29 and 30, the contactrings 2910 may be separated by dielectric separator rings 2920 and mayhave a contact guide cap 2930 similar to embodiments illustrated inFIGS. 19-22. In some embodiments, the contact rings and contact guidecap, such as the contact rings 2910 and contact guide cap 2930, may beformed with beveled edges. In such embodiments a smaller diameterseparator ring, such as the dielectric separator rings 2920, may be usedso as to allow the contact rings to protrude further outward. Suchgeometry of contact rings, guide caps, and separator rings may aid inpreventing unnecessary wear of contacts on the PCB brushes such as theleft PCB brush 2810 and the right PCB brush 2820.

In one aspect, use of slip rings as described herein may advantageouslyallow smaller and/or lighter camera heads or other devices whereelectrical contacts between moving elements need to be maintained. Forexample, FIG. 33 illustrates reduction of size as may be implemented ina camera head embodiment 3320 in accordance with aspects disclosedherein. Camera head 3320 includes a slip ring embodiment as describedherein, as well as counterweight size and mass reduction. Camera head3310 is a prior art camera head using a traditional slip ringconfiguration. Both camera heads are shown with coins to illustratetheir sizes and the size reduction of camera head 3320.

FIG. 34 illustrates details of internal components of camera head 3320,including a cylindrical ring assembly 3410 disposed within a selfleveling case embodiment 3400, which may correspond with case 350 asdescribed previously herein.

FIG. 35 illustrates a corresponding brush module embodiment showingbrush elements 3510. In the assembled configuration, the cylindricalring assembly 3410 is positioned at location 3505, relative to the twobrush elements 3510.

FIG. 36 illustrates an embodiment of a brush element 3510 showing threefingers or tines with electrical contacts in the form of printed circuitboard traces disposed thereon.

Various embodiments of the disclosures described herein may be used todecrease the size of camera heads and provide additional advantages,such as reducing required weights to mechanically self-level the camerahead due to decreased rotational contact areas in bearings or othermoving components. Some embodiments in accordance with aspects describedherein may be advantageous in implementing highly miniaturized and/orlightweight camera heads and associated inspection systems.

The claims of the present invention are not intended to be limited tothe aspects shown herein, but are to be accorded the full scopeconsistent with the language and drawings herein, wherein reference toan element in the singular is not intended to mean “one and only one”unless specifically so stated, but rather “one or more.” Unlessspecifically stated otherwise, the term “some” refers to one or more. Aphrase referring to “at least one of a list of items refers to anycombination of those items, including single members. As an example, “atleast one of: a, b, or c” is intended to cover: a; b; c; a and b; a andc; b and c; and a, b and c.

The previous description of the disclosed aspects is provided to enableany person skilled in the art to make or use embodiments of thepresently claimed invention. Various modifications to these aspects willbe readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other aspects withoutdeparting from the spirit or scope of the invention. Thus, the presentlyclaimed invention is not intended to be limited to the aspects shownherein but is to be accorded the widest scope consistent with theappended claims and their equivalents.

We claim:
 1. A camera head, comprising: a housing; an imager disposedwithin the housing on a first element movable relative to the housing; asecond element rotationally movable relative to the first element, thesecond element including an electrical output connection; and a slipring coupled between the first element and the second element to providean electrical connection between an output of the imager and theelectrical output connection, wherein the slip ring comprises: acylindrical ring assembly including one or more ring electricalcontacts; and a brush assembly disposed around the cylindrical ringassembly, the brush assembly including a brush element including aplurality of tines or fingers including electrical contacts, wherein oneor more of the brush electrical contacts are positioned in contact withcorresponding ones of the one or more ring electrical contacts.
 2. Thecamera head of claim 1, further including a counterweight to self-levelthe imaging sensor via gravity.
 3. The camera head of claim 1, whereinthe brush assembly comprises a brush element, wherein the brushelectrical contacts are on or within the brush element.
 4. The camerahead of claim 1, wherein the electrical contacts are electrical circuittraces on the tines or fingers.
 5. The camera head of claim 3, whereinthe fingers or tines of the brush elements are interleaved in the brushassembly.
 6. The camera head of claim 3, wherein the brush elementcomprises a printed circuit board (PCB) and the electrical contacts areelectrically conductive areas on the PCB.
 7. The camera head of claim 6,wherein the electrically conductive areas on the PCB are circuit traces.8. The camera head of claim 1, wherein the brush electrical contacts arecoated with one or more of palladium, nickel, rhodium, and hard gold todecrease frictional contact erosion and/or corrosion.
 9. The camera headof claim 1, wherein the cylindrical ring assembly includes one or morecontact rings.
 10. The camera head of claim 9, wherein the cylindricalring assembly includes a plurality of contact rings and one or moredielectric separate rings.
 11. The camera head of claim 10, furtherincluding a contact guide cap.
 12. The camera head of claim 1, furthercomprising a lubricant disposed on a slip contact surface.
 13. Thecamera head of claim 1, further comprising a grease or flypaper placedon internal surfaces to scavenge dirt and debris.
 14. The camera head ofclaim 13, wherein the grease or flypaper is disposed on one or morecontact surfaces of the slip ring.
 15. The camera head of claim 1,wherein at least one of the electrical connections is soldered with alow temperature, compliant solder.
 16. The camera head of claim 15,wherein the low temperate, compliant solder comprises one or more ofAlpha WS-852, Indium Corp. alloys 281, and Indium Corp. alloys
 282. 17.The camera head of claim 1, further comprising a desiccant material toremove moisture.
 18. The camera head of claim 1, wherein the position ofthe rings and brushes are interchanged.
 19. The camera head of claim 1,wherein the camera head includes one or more bearings.
 20. The camerahead of claim 19, wherein the bearing are ball bearings includingceramic balls.
 21. The camera head of claim 1, wherein the rings arefabricated using an oven reflow soldering process.